[Effect of population immunity against hepatitis A in day-care centers]

J H Fan1

  • 1Department of Epidemiology, Fourth Military Medical University, Xi'an.

The authors investigated 21 groups with hepatitis A (HA) introduction into 16 day-care centers in a district of Xi'an, studied the infection condition and the effect of population immunity against HA on the HA transmission. The results showed that when the level of population immunity prior to HA introduction was below 50 percent, population immunity played no significant role in the HA transmission.

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